DEFEND
};
-/* Implicitly zero-initialized */
-static const struct in_addr null_ip;
-static const struct ether_addr null_addr;
-static int verbose;
-
-#define DBG(fmt,args...) \
+#define VDBG(fmt,args...) \
do { } while (0)
-#define VDBG DBG
+
+static unsigned opts;
+#define FOREGROUND (opts & 1)
+#define QUIT (opts & 2)
/**
* Pick a random link local IP address on 169.254/16, except that
*/
static void pick(struct in_addr *ip)
{
- unsigned tmp;
+ unsigned tmp;
/* use cheaper math than lrand48() mod N */
do {
ip->s_addr = htonl((LINKLOCAL_ADDR + 0x0100) + tmp);
}
+/* TODO: we need a flag to direct bb_[p]error_msg output to stderr. */
+
/**
* Broadcast an ARP packet.
*/
-static int arp(int fd, struct sockaddr *saddr, int op,
+static void arp(int fd, struct sockaddr *saddr, int op,
const struct ether_addr *source_addr, struct in_addr source_ip,
const struct ether_addr *target_addr, struct in_addr target_ip)
{
// send it
if (sendto(fd, &p, sizeof (p), 0, saddr, sizeof (*saddr)) < 0) {
- perror("sendto");
- return -errno;
+ bb_perror_msg("sendto");
+ //return -errno;
}
- return 0;
+ // Currently all callers ignore errors, that's why returns are
+ // commented out...
+ //return 0;
}
/**
* Run a script.
- * TODO: sort out stderr/syslog reporting.
*/
static int run(char *script, char *arg, char *intf, struct in_addr *ip)
{
int pid, status;
char *why;
- if (script != NULL) {
+ if(1) { //always true: if (script != NULL)
VDBG("%s run %s %s\n", intf, script, arg);
if (ip != NULL) {
char *addr = inet_ntoa(*ip);
setenv("ip", addr, 1);
- syslog(LOG_INFO, "%s %s %s", arg, intf, addr);
+ bb_info_msg("%s %s %s", arg, intf, addr);
}
pid = vfork();
goto bad;
} else if (pid == 0) { // child
execl(script, script, arg, NULL);
- perror("execl");
+ bb_perror_msg("execl");
_exit(EXIT_FAILURE);
}
goto bad;
}
if (WEXITSTATUS(status) != 0) {
- bb_error_msg("script %s failed, exit=%d\n",
- script, WEXITSTATUS(status));
+ bb_error_msg("script %s failed, exit=%d",
+ script, WEXITSTATUS(status));
return -errno;
}
}
return 0;
bad:
status = -errno;
- syslog(LOG_ERR, "%s %s, %s error: %s",
- arg, intf, why, strerror(errno));
+ bb_perror_msg("%s %s, %s", arg, intf, why);
return status;
}
* main program
*/
+/* Used to be auto variables on main() stack, but
+ * most of them were zero-inited. Moving them to bss
+ * is more space-efficient.
+ */
+static const struct in_addr null_ip; // = { 0 };
+static const struct ether_addr null_addr; // = { {0, 0, 0, 0, 0, 0} };
+
+static struct sockaddr saddr; // memset(0);
+static struct in_addr ip; // = { 0 };
+static struct ifreq ifr; //memset(0);
+
+static char *intf; // = NULL;
+static char *script; // = NULL;
+static suseconds_t timeout; // = 0; // milliseconds
+static unsigned conflicts; // = 0;
+static unsigned nprobes; // = 0;
+static unsigned nclaims; // = 0;
+static int ready; // = 0;
+static int verbose; // = 0;
+static int state = PROBE;
+
int zcip_main(int argc, char *argv[])
{
- char *intf = NULL;
- char *script = NULL;
- int quit = 0;
- int foreground = 0;
-
+ struct ether_addr eth_addr;
char *why;
- struct sockaddr saddr;
- struct ether_addr addr;
- struct in_addr ip = { 0 };
int fd;
- int ready = 0;
- suseconds_t timeout = 0; // milliseconds
- unsigned conflicts = 0;
- unsigned nprobes = 0;
- unsigned nclaims = 0;
- int t;
- int state = PROBE;
-
- struct ifreq ifr;
- unsigned short seed[3];
// parse commandline: prog [options] ifname script
- while ((t = getopt(argc, argv, "fqr:v")) != EOF) {
- switch (t) {
- case 'f':
- foreground = 1;
- continue;
- case 'q':
- quit = 1;
- continue;
- case 'r':
- if (inet_aton(optarg, &ip) == 0
- || (ntohl(ip.s_addr) & IN_CLASSB_NET)
- != LINKLOCAL_ADDR) {
- bb_error_msg_and_die("invalid link address");
- }
- continue;
- case 'v':
- verbose++;
- foreground = 1;
- continue;
- default:
- bb_error_msg_and_die("bad option");
- }
+ char *r_opt;
+ opt_complementary = "vv:vf"; // -v accumulates and implies -f
+ opts = getopt32(argc, argv, "fqr:v", &r_opt, &verbose);
+ if (!FOREGROUND) {
+ /* Do it early, before all bb_xx_msg calls */
+ logmode = LOGMODE_SYSLOG;
+ openlog(bb_applet_name, 0, LOG_DAEMON);
}
- if (optind < argc - 1) {
- intf = argv[optind++];
- setenv("interface", intf, 1);
- script = argv[optind++];
+ if (opts & 4) { // -r n.n.n.n
+ if (inet_aton(r_opt, &ip) == 0
+ || (ntohl(ip.s_addr) & IN_CLASSB_NET) != LINKLOCAL_ADDR) {
+ bb_error_msg_and_die("invalid link address");
+ }
}
- if (optind != argc || !intf)
+ argc -= optind;
+ argv += optind;
+ if (argc != 2)
bb_show_usage();
- openlog(bb_applet_name, 0, LOG_DAEMON);
+ intf = argv[0];
+ script = argv[1];
+ setenv("interface", intf, 1);
// initialize the interface (modprobe, ifup, etc)
if (run(script, "init", intf, NULL) < 0)
return EXIT_FAILURE;
// initialize saddr
- memset(&saddr, 0, sizeof (saddr));
+ //memset(&saddr, 0, sizeof (saddr));
safe_strncpy(saddr.sa_data, intf, sizeof (saddr.sa_data));
// open an ARP socket
fd = xsocket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ARP));
// bind to the interface's ARP socket
- xbind(fd, &saddr, sizeof (saddr);
+ xbind(fd, &saddr, sizeof (saddr));
// get the interface's ethernet address
- memset(&ifr, 0, sizeof (ifr));
+ //memset(&ifr, 0, sizeof (ifr));
strncpy(ifr.ifr_name, intf, sizeof (ifr.ifr_name));
if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
- foreground = 1;
- why = "get ethernet address";
- goto bad;
+ bb_perror_msg_and_die("get ethernet address");
}
- memcpy(&addr, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
+ memcpy(ð_addr, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
// start with some stable ip address, either a function of
// the hardware address or else the last address we used.
// NOTE: the sequence of addresses we try changes only
// depending on when we detect conflicts.
- memcpy(seed, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
- seed48(seed);
+ // (SVID 3 bogon: who says that "short" is always 16 bits?)
+ seed48( (unsigned short*)&ifr.ifr_hwaddr.sa_data );
if (ip.s_addr == 0)
pick(&ip);
// - link already has local address... just defend/update
// daemonize now; don't delay system startup
- if (!foreground) {
- xdaemon(0, verbose);
- syslog(LOG_INFO, "start, interface %s", intf);
+ if (!FOREGROUND) {
+ setsid();
+ xdaemon(0, 0);
+ bb_info_msg("start, interface %s", intf);
}
// run the dynamic address negotiation protocol,
struct timeval tv1;
struct arp_packet p;
+ int source_ip_conflict = 0;
+ int target_ip_conflict = 0;
+
fds[0].fd = fd;
fds[0].events = POLLIN;
fds[0].revents = 0;
- int source_ip_conflict = 0;
- int target_ip_conflict = 0;
-
// poll, being ready to adjust current timeout
if (!timeout) {
timeout = ms_rdelay(PROBE_WAIT);
tv1.tv_sec++;
}
tv1.tv_sec += timeout / 1000;
-
+
VDBG("...wait %ld %s nprobes=%d, nclaims=%d\n",
timeout, intf, nprobes, nclaims);
switch (poll(fds, 1, timeout)) {
VDBG("state = %d\n", state);
switch (state) {
case PROBE:
- // timeouts in the PROBE state means no conflicting ARP packets
+ // timeouts in the PROBE state mean no conflicting ARP packets
// have been received, so we can progress through the states
if (nprobes < PROBE_NUM) {
nprobes++;
VDBG("probe/%d %s@%s\n",
nprobes, intf, inet_ntoa(ip));
- (void)arp(fd, &saddr, ARPOP_REQUEST,
- &addr, null_ip,
+ arp(fd, &saddr, ARPOP_REQUEST,
+ ð_addr, null_ip,
&null_addr, ip);
timeout = PROBE_MIN * 1000;
timeout += ms_rdelay(PROBE_MAX
nclaims = 0;
VDBG("announce/%d %s@%s\n",
nclaims, intf, inet_ntoa(ip));
- (void)arp(fd, &saddr, ARPOP_REQUEST,
- &addr, ip,
- &addr, ip);
+ arp(fd, &saddr, ARPOP_REQUEST,
+ ð_addr, ip,
+ ð_addr, ip);
timeout = ANNOUNCE_INTERVAL * 1000;
}
break;
case RATE_LIMIT_PROBE:
- // timeouts in the RATE_LIMIT_PROBE state means no conflicting ARP packets
+ // timeouts in the RATE_LIMIT_PROBE state mean no conflicting ARP packets
// have been received, so we can move immediately to the announce state
state = ANNOUNCE;
nclaims = 0;
VDBG("announce/%d %s@%s\n",
nclaims, intf, inet_ntoa(ip));
- (void)arp(fd, &saddr, ARPOP_REQUEST,
- &addr, ip,
- &addr, ip);
+ arp(fd, &saddr, ARPOP_REQUEST,
+ ð_addr, ip,
+ ð_addr, ip);
timeout = ANNOUNCE_INTERVAL * 1000;
break;
case ANNOUNCE:
- // timeouts in the ANNOUNCE state means no conflicting ARP packets
+ // timeouts in the ANNOUNCE state mean no conflicting ARP packets
// have been received, so we can progress through the states
if (nclaims < ANNOUNCE_NUM) {
nclaims++;
VDBG("announce/%d %s@%s\n",
nclaims, intf, inet_ntoa(ip));
- (void)arp(fd, &saddr, ARPOP_REQUEST,
- &addr, ip,
- &addr, ip);
+ arp(fd, &saddr, ARPOP_REQUEST,
+ ð_addr, ip,
+ ð_addr, ip);
timeout = ANNOUNCE_INTERVAL * 1000;
}
else {
conflicts = 0;
timeout = -1; // Never timeout in the monitor state.
- // NOTE: all other exit paths
+ // NOTE: all other exit paths
// should deconfig ...
- if (quit)
+ if (QUIT)
return EXIT_SUCCESS;
}
break;
if (fds[0].revents & POLLERR) {
// FIXME: links routinely go down;
// this shouldn't necessarily exit.
- bb_error_msg("%s: poll error\n", intf);
+ bb_error_msg("%s: poll error", intf);
if (ready) {
run(script, "deconfig",
intf, &ip);
continue;
if (memcmp(p.arp.arp_spa, &ip.s_addr, sizeof(struct in_addr)) == 0 &&
- memcmp(&addr, &p.arp.arp_sha, ETH_ALEN) != 0) {
+ memcmp(ð_addr, &p.arp.arp_sha, ETH_ALEN) != 0) {
source_ip_conflict = 1;
}
if (memcmp(p.arp.arp_tpa, &ip.s_addr, sizeof(struct in_addr)) == 0 &&
p.arp.arp_op == htons(ARPOP_REQUEST) &&
- memcmp(&addr, &p.arp.arp_tha, ETH_ALEN) != 0) {
+ memcmp(ð_addr, &p.arp.arp_tha, ETH_ALEN) != 0) {
target_ip_conflict = 1;
}
- VDBG("state = %d, source ip conflict = %d, target ip conflict = %d\n",
+ VDBG("state = %d, source ip conflict = %d, target ip conflict = %d\n",
state, source_ip_conflict, target_ip_conflict);
switch (state) {
case PROBE:
VDBG("monitor conflict -- defending\n");
state = DEFEND;
timeout = DEFEND_INTERVAL * 1000;
- (void)arp(fd, &saddr,
+ arp(fd, &saddr,
ARPOP_REQUEST,
- &addr, ip,
- &addr, ip);
+ ð_addr, ip,
+ ð_addr, ip);
}
break;
case DEFEND:
} // switch poll
}
bad:
- if (foreground)
- perror(why);
- else
- syslog(LOG_ERR, "%s %s, %s error: %s",
- bb_applet_name, intf, why, strerror(errno));
+ bb_perror_msg("%s, %s", intf, why);
return EXIT_FAILURE;
}
projects / oweals / busybox.git / blobdiff